1. Field of the Invention
The present invention relates to a cleaning device, and more particularly, to a device for cleaning a liquid crystal display (LCD) panel for effective removal of foreign matters after grinding the LCD panel.
2. Discussion of the Related Art
The fields of use for LCD's have gradually increased since LCD's have overcome many of the disadvantages of the CRT (Cathode Ray Tube). The increase in use is due to the advantages of the LCD such as great contrast ratio, suitable for expression of gradation and display of a motion picture, and small power consumption.
The LCD panel is generally provided with a thin film transistor substrate having a thin film transistor and a pixel electrode in every pixel region defined by gatelines and datalines, a color filter substrate having a color filter layer and a common electrode, and a liquid crystal layer between the two substrates.
A related art device for cleaning a LCD panel will be explained with reference to the attached drawings.
FIG. 1 illustrates a perspective view of a related art cleaning device, and FIG. 2 illustrates a side view of the related art cleaning device.
Referring to FIG. 1, in general, the cleaning device is provided with a plurality of brushes 1 over a substrate 4 to be cleaned, driving shafts 2 each for holding and rotating the brush, a driving motor (not shown) for rotating the driving shafts 2, a plurality of transfer rollers 6 under the substrate 4 to be cleaned for transfer of the substrate 4, and rotation shafts 7 for rotating the transfer rollers in one direction. The cleaning device rotates the brushes 1 in a direction, the same with, or opposite to, a direction of movement of the substrate 4, for cleaning the substrate 4.
However, the cleaning device has the following problems in removing foreign matters on the LCD panel passed through grinding.
Referring to FIG. 2, the LCD panel 10 has an upper substrate 10a and a lower substrate 10b, both of which are bonded together, and a liquid crystal layer between the substrates. Consequently, since the brush 1 brushes only a surface of the LCD panel, i.e., only the substrate 10a, without being brought into contact with a pad part 5 of the lower substrate 10b comparatively below the upper substrate 10a, foreign matters on the pad part 5 are not removed. Although the foreign matters on the pad part 5 may be removed by an ultrasonic wave, the effect is not satisfactory.
The foreign matters not removed cause scratches on the surface of the substrate, or shorts between pad part patterns, impeding regular operation of the LCD panel.